The purpose of this study is to collect blood specimens and clinical data from screening guideline eligible individuals designated by their physician to receive a screening colonoscopy, and to evaluate the performance of a colorectal cancer-specific DNA methylation biomarker for detection of colorectal cancer in this cohort. Based on the outcome of the colonoscopy, polypectomy, biopsy and surgical tissue histopathology, the clinical utility of Septin 9 as colorectal cancer screening test will be evaluated.